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<b>DB_ENV-&gt;set_isalive</b>
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<b><pre>
#include &lt;db.h&gt;
<p>
int
DB_ENV-&gt;set_isalive(DB_ENV *dbenv,
    int (*is_alive)(DB_ENV *dbenv, pid_t pid, db_threadid_t tid, u_int32_t flags));
</pre></b>
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<b>Description: DB_ENV-&gt;set_isalive</b>
<p>Declare a function that returns if a thread of control (either a true
thread or a process) is still running.  The DB_ENV-&gt;set_isalive method
supports the <a href="../api_c/env_failchk.html">DB_ENV-&gt;failchk</a> method.  For more information, see
<a href="../ref/cam/app.html">Architecting Data Store and Concurrent
Data Store applications</a>, and <a href="../ref/transapp/app.html">Architecting Transactional Data Store applications</a>.</p>
<p>The DB_ENV-&gt;set_isalive method configures operations performed using the specified
<a href="../api_c/env_class.html">DB_ENV</a> handle, not all operations performed on the underlying
database environment.</p>
<p>The DB_ENV-&gt;set_isalive method may be called at any time during the life of the
application.</p>
<p>The DB_ENV-&gt;set_isalive method
returns a non-zero error value on failure
and 0 on success.
</p>
<b>Parameters</b> <br>
 <b>is_alive</b><ul compact><li>The <b>is_alive</b> parameter is a function which returns non-zero if
the thread of control, identified by the <b>pid</b> and <b>tid</b>
arguments, is still running.  The function takes four arguments:</ul>
<br>
<b><b>dbenv</b></b><ul compact><li>The <b>dbenv</b> parameter is the enclosing database environment
handle, allowing application access to the application-private fields
of that object.</ul>
<b><b>pid</b></b><ul compact><li>The <b>pid</b> parameter is a process ID returned by the function
specified to the <a href="../api_c/env_set_thread_id.html">DB_ENV-&gt;set_thread_id</a> method.</ul>
<b><b>tid</b></b><ul compact><li>The <b>tid</b> parameter is a thread ID returned by the function
specified to the <a href="../api_c/env_set_thread_id.html">DB_ENV-&gt;set_thread_id</a> method.</ul>
<b><b>flags</b></b><ul compact><li>The <b>flags</b> parameter must be set to 0 or
the following value:
<br>
<b><a name="DB_MUTEX_PROCESS_ONLY">DB_MUTEX_PROCESS_ONLY</a></b><ul compact><li>Return only if the process is alive, the thread ID should be ignored.</ul>
<br></ul>
<br>
<br>
<br><b>Errors</b>
<p>The DB_ENV-&gt;set_isalive method
may fail and return one of the following non-zero errors:</p>
<br>
<b>EINVAL</b><ul compact><li>An
invalid flag value or parameter was specified.</ul>
<br>
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<br><b>Class</b>
<a href="../api_c/env_class.html">DB_ENV</a>
<br><b>See Also</b>
<a href="../api_c/env_list.html">Database Environments and Related Methods</a>
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